Who uses race gas

[Woody_393]

Here's another interesting tidbit I found from www.briggsracing.com. Pay attention to the bold, italics and Red parts. I think you will find it very interesting. I know I did.

"Octane Rating

The octane rating is a numbering system based on Isooctane = 100. The number determines the relative ability for the fuel to produce knock in the engine. The higher the number the less tendency for knock.

It is evident that the octane rating also has an effect upon the speed at which the fuel burns. The desire is to have the fuel to burn as rapidly as possible without creating damaging shock waves produced from preignition. The rapid burning will produce higher combustion pressure of the piston therefore creating a higher output of power.

The octane rating is not the only element that controls the rate of the burn. The air/fuel ratio, the valve configuration, and the shape and size of the combustion chamber will all have an effect on the rate of burn.

This would indicate to get the maximum output the lowest octane rated fuel must be used which will not cause preignition. Remember that as components are changed in the engine the fuel that is required may also change."

[Yardpro393]

way to go woody.

i have always argued that point to people. i can't tell you how many people i know have bought race gas and said thier bike screamed with it. not being able to controil my mouth i would always spout off that they were full of crap, and they were only mentally justifying the $8.00/gallon they paid.

[4strkepwr660R]

I just use 94 Octane Pump Gas.

[Woody_393]

Thanks YP. It is amazing how many people think Octane will make them faster. This is an all too common misconception.

KB?

[MXCOP]

Woody and YP-
I know you guys are on thumpers now but have you ever talked to anyone that has used Ultimate 2 the 2 stroke version of Ultimate 4?

[Woody_393]

Isn't ulitmate 2 and 4 the oxygenated gas from vp? If it is, the extra oxygen does help HP, but it's the oxygen not the octane that helps.

[VET393]

I use 93 and sometimes have to look for it, but I keep track of the stations that have it.

[Dell30rb]

93 is all you can get around here, never seen 91 premium.

I ran octane booster for awhile, my picky stock cr125 motor was pinging. I stuck two base gaskets in on the last topend to raise the cylinder and lower the compression. And then i quit running the booster. Personally I think the stuff is crap, only run it when you have to.

[YZ rider 77662]

I just finished reading this thread and figured I would throw in my two cents,not that it matters or anything.I ride a yz 125 and run a marine race fuel called C12 now I can say that there is a noticable differance in the way my bike runs with it and with pump gas.The C12 seems to give the bike a break neck throttle response and it feels to run a whole lot smoother and cleaner than pump gas.I've also tried octane booster in pump gas as described above and tried mixing it to various ratios,but couldn't tell much of a differance as if I had used it or not.I've also ran C12 in a 4-stroke bike and couldn't tell that much of a differance also.Maybe it's just a 2-stroke thing,but C12 and Motuls is my magic potion.

[monkeyonahill]

Alright, when i first bought my '03 YZF 250 about 2 months ago i think it had 104 octane race gas, im not sure on the octane rating, but it was expensive race gas.. the guy i bought it from owns a petrolium company, so he got it cheap. and after i ran the 2 gallons of race gas i switched to 92/93 octane pump gas, and i couldn't tell a power difference at all. the only thing different is there wasn't a sweet scent in the exhaust, lol. Just thought i'd throw that in. i'm sticking to pump + some octane booster everyonce in a while, until i start getting into the engine.

[xr250r]

yea well i can say race fuek helps modded motors alot because i drove my neigbors machz1000 2 stroke sled on premium gas and it was amazing then he added c-14 and it was like strappin a jet engine on to it all he had done at teh time was clutching and high comp heads now he has nos and pulls wheelies at 140+mph before running out of lake the thing is nuts

[Racer92]

Standard automotive gasoline products provide enough detonation resistance for OEM dirt bike engines. (unless you start altering compression or timing events)

The only thing a person need be concerned with regarding ANY gasoline product is the distillation curve: the beginning, mid, and endpoint. This is where specially blended gasolines ARE different and more suited for a given application.

If you do not understand what is going on regarding that curve, you are missing the point entirely of stoichiometric combustion.

[harticat]

Originally Posted by xr250r

yea well i can say race fuek helps modded motors alot because i drove my neigbors machz1000 2 stroke sled on premium gas and it was amazing then he added c-14 and it was like strappin a jet engine on to it all he had done at teh time was clutching and high comp heads now he has nos and pulls wheelies at 140+mph before running out of lake the thing is nuts

Your neighbor must have a sled faster than Modzilla (world record holder at192 mph and over 750 HP)!!!! If the neighbor's sled can pull the skis off the ground at 140 mph with clipped heads, clutch work and race gas, then he must be hiding a world record sled........

[2kHondaCR500R]

Race fuel is a waste of money to put in an engine that doesn't need it (high compression modified engines).

As a side note, I run a high comp head and need it for that setup. For 10 gallons of VP C12 yesterday, I had to fork out just over $144.xx and that puts it at $14.4x a gallon.

Needless to say and as much as I hate to, I'm swapping back to the pump gas dome and rejetting for 93 pump.

[xr250r]

yea he dosent want any publisity he wants him and his sled to be a sleeper so people will race him and be like holy poop that thing is fast

[harticat]

Originally Posted by xr250r

yea he dosent want any publisity he wants him and his sled to be a sleeper so people will race him and be like holy poop that thing is fast

I would think that if someone has a sled that is as fast as you claim, they would want to be the world record holder and want the notoriety....

[dlowe102]

i use cam2 wich is leaded 110 octane it costs $8.00 a gallon ive ran it for 10 years in all my bikes and i never never had a single top end issue ever.....i at one time mixed 1 part pump to 3 parts race to lower the octane until i got a bad batch of pump gas ...i dont play with pump gas at all now there is a legal amount of filler that stations dont have to post that wont affect a multi cylinder motor....not something i wont jumping 100 foot jumps on a 250 but whatever fuel you use i believe the lead as a lubricant will be better for your motor.

[kschilk]

Speed & power comes from what you do with that li'l twisty thing, on the right side of the handlebar....not from what ya' put in the tank. Designer fuels, accessories and gear will make you poor, they don't make you fast. There's no way around it...you can't buy speed, ya' gotta' earn it.

[racerfty]

Check this site out,
[Only registered and activated users can see links. ]
It sums it all up easily understood

[mephistopheles]

Originally Posted by Mikelehmann

looking at honda web page shows the CR250F with 13 to1 12.9 for those that are picky no way will pump gas support that compresstion

It will. The shape of the head and the material used have a lot to do with it. If you made that statement back in the 60's and 70's it would have been true. Now, with aluminum heads/cylinders with their greater heat transferring capabilities and head design, it is now very common to be able to run pump gas at these compression ratios.